Switch



Patented Mar. 21, 1950 SWITCH John P. Smith, Jr., Verona, N. J assignor to The Daven Company, Newark, N. J a corporation of New Jersey Application May 18, 1948. Serial No. 27,722

8 Claims. 1

This invention relates to electrical switches, of the step-by-step type principally employed for volume control in the communications field.

There are certain installations wherein the employment of the cylindrical rotary type of switches, potentiometers or the like, are not practical or convenient to use and where it is desired to position a number of such instruments in close proximity one to another, and an object of the present invention is to provide a fiat instrument, adjustment of which is obtained by moving a pivoted lever, the setting of which lever is indicated by its position along a linear dial having indicating numbers thereon in vertical position and in one line. A number of such instruments of the presentv invention may be mounted in close parallel arrangement with all of their operating levers in convenient accessible position for ease and speed of operation.

Another object of the present invention is the provision of a flat electrical switch or the like, which is entirely enclosed inv a protective housing of simple and unique construction, with the contacts, movable switch blades and co-acting parts so located that the cover of the housing may be quickly and easily removed to permit a(:-

cess to the contacts, switch blades, etc., for cleaning, repair or replacement without in any way affecting the wiring connections of the instrument.

A further object of the present invention is to provide an electrical switch or like instrument of the type above referred to which is compact, neat in appearance, provides accurate positive setting or adjustment of the device and one which can be economically manufactured.

With these and other objects in view, as may appear from the accompanying specification. the invention consists of various features of construction and combination of parts, which will be first described in connection with the accompanying drawings, showing a switch of a preferred form embodying the invention, and the features forming the invention will be specifically pointed out in the claims.

. In the drawings: v

Figure l is a perspective view of the improved attenuator, potentiometer or the like.

- Figure 2 is a plan view of the attenuator or the like having the cover of its enclosing housing removed.

Figure 3 is a side elevation of the instrument showingthe housing in section, the housing being sectioned on the line 3-3 of Figure 2.

Figure 4 is a perspective view of the cover for the housing.

Referring more particularly to the drawings, the improved electrical instrument such as an attenuator, potentiometer or the like comprises a flat plate I of any suitable insulating material which is shown in the drawings shaped as a truncated triangle, although the invention is not to be limited to such particular shape.

The insulating plate I has a plurality of independent spaced contacts 2 carried thereby which are arranged in one or more arcuate rows at the base or wider end of the plate I. The contacts 2 are connected, as is usual in instruments of this kind, with the resistance coils 3 and with a suitable source of power (not shown) through certain of the terminal posts 4 carried by the terminal block 5. One or more ring contacts 6 are carried by the plate I intermediate its ends and these contacts are likewise connected in the electrical circuit of the instrument.

A switch member generically indicated by the numeral 1 is provided which comprises a carrying body 8 of insulating material. The carrying body 8 is pivotally mounted by a suitable removable pin 9 at the center or axis of the ring contacts 6. A plurality of sets of spring contact or switch blades II! are carried by the carrying body 8, being attached thereto by suitable attaching means II. As clearly shown in Figures 2 and 3 of the drawings, the switch blades extend in opposite directions from their points of connection with the carrying body 8 and have their terminals bent as shown at I 2 to contact and sweep over the ring contact 6 and the inde pendent contacts 2 so as to close a circuit through certain predetermined independent contacts depending upon the adjustment of the instrument.

The carrying body 8 of the switch member 1 is connected by a pin I3 to an actuating lever I4. The pin I3 rides in a slot I5 extending longitudinally in the actuating lever I4 so as to permit limited sliding movement of the pin relative to the actuating lever It to provide for the proper operation of the device. The actuating lever I4 is pivoted at its inner end and in close proximity to the smallend of the plate I to a supporting block l6 which is attached to the insulation plate I in any suitable manner such as by studs, as shown in Figure 3 of the drawings. The supporting block l6 also serves to space the actuating lever I4 from the insulation plate to a suflicient distance to permit it to clear the switch member 1 during operation of the lever.

A front plate H, which has an arcuate outer surface is attached to the insulation plate I by suitable attaching blocks l8 and studs I8. This front cover plate ll is provided with a slot 19 through which the end of the actuating lever l4 extends. An operating knob 20 is mounted upon the end of the lever M which projects through the slot l9. An indicating pointer 2| is carried by the lever l4 outwardly of the front plate ll and it cooperates with a linear dial 22 which is carried by the front plate IT. The linear dial 22 is graduated to indicate the various settings of the actuating lever 14 and, consequently, of the switch member I. I 1

The actuating lever I4 has a resilient bumper 23 attached thereto which contacts stops 24 carried by the insulation plate I.

An enclosing housing is provided for protecting various elements of the instrument and it comprises the housing section 25 which is attached by suitable studs 26 and posts 21 to the insulation plate I. The housing section 25 extends to the under surface of the insulation plate I as clearly shown in Figure 3 of the drawings and it en closes the various resistance coils 3 and their Wiring connections with the terminal posts 4, all

of which elements are positioned on one side of the insulation plate I, leaving the independent contacts 2, ring contacts 6. switch member l and actuating lever l4 exposed as they are all positioned on the side of the insulation. plate l opposite from the resistance coils 3.- The terminal block 5 which carries the terminal post A is made of insulating material and it has slots 28 cut in its ends which receive the edges of one sidewall of the housing or cam 25, which edges form the ends of a cutout portion which receives the terminal block 5. This construction is clearly shown in Figure 2 of the drawings and thus the terminal block 5 is connected to the housing 25 by sliding it into the cutout portion in the side 29 of the housing.

A removable cover 30 is provided for enclosing the contact elements, switch member and actuating lever and it comprises the top 3| with the pendant sides 32, one of which is provided with a cutout 33 which fits over the terminal block 5. The end 34 of the cover 30 has an opening 35 therein through which a threaded attaching stud 36 extends. The stud 3'6 threads into the spacing block l6 and the sides 32 of the cover fit snugly against the upstanding sides of the section 25 of the housing with the open end of the cover snugly fitting against the front plate l'l. Thus by removal of the stud 3B the cover 3!! may be removed to permit ready access to the contacts,

switch member and actuating lever.

It will be understood that the invention is not to be limited to the specific construction or arrangement of parts shown, but that they may be widely modified within the invention defined by the claims.

What is claimed is:

1. In an electrical switch, an insulating plate, an arcuate row of contacts carried by said plate,

an arcuate contact carried by said plate inter mediate its ends, a selective switch member pi v otally connected at one of its ends to said plate at the axis of said arcuate contact. a spring switch blade carried by said switch member for establishing electrical current conducting contact with said arcuate contact and any selected one of said individual contacts, and an operating lever pivotally connected at one end to said plate and pivotally and slidably connected intermediate its ends to the end of said switch member remote from its pivotal axis.

2. In an electrical switch, a housing having one side and one end open, an insulating plate, spacing posts for supporting said plate within the housing in spaced relation to the closed side of the housing, an arcuate row of independent contacts carried by said plate on the side facing the open side of the housing and near one end of the plate, an arcuate contact on the side of said plate facing the open side of the housing, a selective switch member pivotally carried by said plate with its pivotal axis at the axis of said arcuate contact, a supporting block carried at the end of said plate remote from said independent contacts and on the same side of the plate as said contacts, an operating lever pivoted to said block, means pivotally and slidably connecting said operating lever to said switch element at the end thereof remote from its pivotal axis, a removable cover plate for the open side of said housing, whereby by removal of the cover plate access may be had to said contact switch member and operating lever.

3. An electrical switch as claimed in claim 2 wherein said selective switch member comprises a carrying body of insulating material and a contact blade attached to said carrying body intermediate its ends and having its ends projecting beyond the ends of the carrying bod for engagement with said arcuate contact and any selected one of said independent contacts.

4. In an electrical switch, a single insulation plate, a plurality of independent contacts arranged in an arcuate row near one end of said plate, an arcuate contact carried by said plate intermediate of its ends, a selective switch member including a carrying body of insulation pivoted to said insulation plate with its axis at the axis of said arcuate contact, a spring switch member carried by said selective switch carrying body and projecting from opposite ends thereof for engagement with the arcuate contact and with any selected one of said independent contacts, and an actuating lever pivotally carried by said plate, and means slidably and pivotally connect-- ing said actuating lever to the end of said selective switch carrying body remote from its pivotal axis.

5. In an electrical switch, a single insulation plate, a plurality of independent contacts arranged in an arcuate row near one end of said plate, a plurality of arcuate contacts intermediate of its ends. said arcuate contacts having a common axis, a selective switch member including an elongated carrying body pivotally connected at one end to said insulation plate at the axis of said arcuate contacts, a plurality of spring contact blades attached to said selective switch carrying body at each side edge thereof and projecting beyond the switch carrying body to establish electrical current conducting contact between the arcuate contacts and any selected ones of said independent contacts.

6. An electrical instrument as claimed in claim 1 wherein said contacts selective switch member and said operating lever are all located on the same side of said plate, a housing enclosing said instrument and open at the side of said plate on which said contacts selective switch and operating lever are located, and a removable cover for the open side of said housing.

7. In an electrical instrument of the type described, an insulating plate, an arcuate row of independent contacts carried by said plate near one end thereof, a. circular contact carried by said plate intermediate its ends, a pivotally movable selective switch member having its pivot at the center point of said circular contact and slidable over said circular and independent contacts, an actuating lever pivotally supported near the end of said plate remote from said arcuate row of independent contacts, means providing a limited sliding connection between said operating lever and said selective switch member to operate the selective switch member on pivotal movement of the lever, a front plate provided with a slot therein through which the free end of said actuating lever extends, a dial on said front plate, and an indicator carried by said operating lever and cooperating with said dial.

8. An electrical instrument as claimed in claim '7 wherein said selective switch comprises an in- REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 361,778 Reynolds Apr. 26, 1887 1,815,633 Peterson July 21, 1931 2,167,237 Gove July 25, 1939 2,449,019 Smith Sept. '7, 1948 

